Many industrial applications require the use of discrete, well-defined and uniform coatings applied to predetermined areas. Such coatings are very useful in varied processes, such as conformal coatings on non-uniform or irregular substrates like electronic circuit boards. In the production of discrete coatings for application to discrete substrate areas, for example, it is desirable to obtain broad, uniform coatings in a non-contact application process with sharp, square, cut-on and cut-off edges with no stringing of material. In particular, conformal coating material is used to protect selected components of a circuit board from moisture, dirt, etc.
A satisfactory coating of a substrate with a material includes both the adequate coverage of the material on the surface of the substrate and the application of the material in a desired amount (e.g., thickness). The two goals are often at odds, since an adjustment made to a parameter of a coating material dispensing system to affect one goal may negatively impact the other goal. For instance, if the pressure of the material supplied to the applicator is raised to increase the width of the fan of material dispensed from the applicator, this may cause the thickness of the material being applied to the substrate to fall to an unacceptable level. Therefore, there is a need for improved systems and methods for applying coating materials to a substrate that account for both the coverage of the material and the amount of material applied.